Controlled release of an antitumor agent from radiation-crosslinked EVA matrices

A.A.A. DE QUEIROZ; G.A. ABRAHAM; O.Z. HIGA

Rio de Janeiro, Brasil

Congreso; World Polymer Congress MACRO2006; 2006

Sociedad Brasileña de Polímeros y I.U.P.A.C.

The effect of g-radiation doses of 12.5 to 380 kGy on the infrared spectra, gel content, mechanical properties, and the release of oxobutyl-5-Fluoro-2'-deoxyuridine (OfdUrd, an antitumor agent) from poly(ethylene-co-vinyl acetate) (EVA) films was studied. The results showed that the application of radiation doses produced a crosslinking reaction leading to a maximum gel content of about 85% in the case of 150 kGy. The mechanical properties of EVA membranes were affected after the exposition to g-radiation. Irradiation dose over 50 kGy caused an increase in the Young’s modulus of EVA and at the same time a decrease in the strain percent. Moreover, the network structure formed after irradiation reduced significantly the OFdUrd release from EVA membranes. In this manner, the radiation dose applied to the polymeric matrix modulated the release of OFdUrd avoiding the high concentrations that may cause severe systemic toxicity. The loading of OFdUrd to EVA matrices triggered a slight hyperemia after implantation, while the inflammatory reaction was only observed during the first two days.